Investigation of the glucosinolates in Hesperis matronalis L. and Hesperis laciniata All.: Unveiling 4'-O-ß-d-apiofuranosylglucomatronalin.

The glucosinolate (GSL) profiles of wild-growing plants from the genus Hesperis, i.e. Hesperis laciniata All. (leaf, stem, flower, and root) from Croatia and Hesperis matronalis L. (leaf, stem, flower, seed, and root) from Canada, were established by LC-MS. During this investigation, 5-(methylsulfanyl)pentyl- (3), 6-(methylsulfanyl)hexyl- (4), 6-(methylsulfinyl)hexyl- (6), and 4'-α-l-rhamnopyranosyloxybenzyl- (17) GSLs were identified. In addition, the presence of 7-(methylsulfinyl)heptyl GSL (18), hydroxy-(α-l-rhamnopyranosyloxy)benzyl GSL, and of one d-apiosylated analogue of 17 were suggested. Moreover, one new GSL, 4'-O-ß-d-apiofuranosylglucomatronalin (19) was isolated from H. laciniata (flower, steam and leaf) and characterized by spectroscopic data interpretation. Finally, we report the presence of 3, 4, 6, 19, glucosinalbin (12), and 4-hydroxyglucobrassicin (20) in H. matronalis and hypothesize the presence of glucomatronalin (13) and 3-hydroxy-6-(methylsulfanyl)hexyl GSL (21).

Antimicrobial and Cytotoxic Activities of Lepidium latifolium L. Hydrodistillate, Extract and Its Major Sulfur Volatile Allyl Isothiocyanate.

The cultivated Lepidium latifolium L. was investigated to decipher its glucosinolate profile, antimicrobial, and cytotoxic activities. HPLC/ESI-MS analyses of the intact glucosinolates and GC/MS analysis of their hydrolysis products showed the presence of sinigrin (1), glucocochlearin (2), glucotropaeolin (3), and 4-methoxyglucobrassicin (4). Hydrodistillate, extract, and allyl isothiocyanate, the main volatile resulting from sinigrin degradation, showed antimicrobial activity against all eleven tested pathogenic and food spoilage bacteria and fungi, with highest effect observed against Candida albicans with MIC50 8 and 16 µg/mL. Hydrodistillate and extract showed the best cytotoxic activity on bladder cancer UM-UC-3 cell line during an incubation time of 24 h (IC50 192.9 and 133.8 µg/mL, respectively), while the best effect on glioblastoma LN229 cell line was observed after 48 h (IC50 110.8 and 30.9 µg/mL, respectively). Pure allyl isothiocyanate displayed a similar trend in cytotoxic effect on both cell lines (IC50 23.3 and 36.5 µg/mL after 24 h and 48 h, respectively).

Applying the hydrodistillation process to Pentadiplandra brazzeana Baill. root: a chemical assessment.

A chemical study of the volatile components obtained by applying the hydrodistillation and reflux processes to Pentadiplandra brazzeana roots was performed by GC-FID and GC-MS. The hydrodistillation process showed a total yield of 0.97% with 0.11% of essential oil and 0.86% of volatile compounds from the aqueous reaction medium; in the reflux process, the volatile extract yield was 1.03%. Benzylic-type isothiocyanates were the major degradation products of glucosinolates in the essential oil (95.0%); the CH2Cl2 extracts obtained from the aqueous solutions were characterised by alcohols and amines in both processes. This study has shown that during hydrodistillation, only 10% of the glucosinolate degradation products are recovered in the essential oil whereas 90% remain in the aqueous medium, being converted into alcohols and amines. The relative percentages of the different chemical classes recovered in our experimental conditions are discussed in relation with the glucosinolate composition in the raw material.

LC-MS profiling of glucosinolates in the seeds of Brassica elongata Ehrh., and of the two stenoendemic B. botteri Vis and B. cazzae Ginzb. & Teyber.

The glucosinolates (GLs) present in seed extracts of Brassica elongata Ehrh., B. botteri Vis and B. cazzae Ginzb. & Teyber from Croatia were identified by LC-MS. 4-Hydroxyindol-3-ylmethyl GL (3) was the major GL in the seeds of B. elongata, along with the four minor GLs 2-(R)-hydroxy-3-butenyl- (1), 3-butenyl- (2), 4-pentenyl- (4) and indol-3-ylmethyl (5). The seeds of B. botteri (Vis island) and B. cazzae (Susac island) contained 2 as the major GL as well as 1, 3, 5 and 4-methoxyindol-3-ylmethyl GL (6). However, the GLs in B. botteri (Palagruza island) differed from other varieties having 2-propenyl GL (7) as the major GL in the seeds, and the four minor GLs 2, 3, 5 and 6. This first report of the GL content in the seeds of B. elongata, B. botteri and B. cazzae indicates that the unique GL profiles could be specific to the geographical origin of the plant.

Probing for the presence of glucosinolates in three Drypetes spp. (Drypetes euryodes (Hiern) Hutch., Drypetes gossweileri S. Moore, Drypetes laciniata Hutch.) and two Rinorea spp. (Rinorea subintegrifolia O. Ktze and Rinorea woermanniana (Büttner) Engl.) from Gabon.

Drypetes euryodes (Hiern) Hutch., Drypetes gossweileri S. Moore, Drypetes laciniata Hutch. (Putranjivaceae), Rinorea subintegrifolia O. Ktze, and Rinorea woermanniana (Büttner) Engl. (Violaceae) from Gabon were probed for the presence of glucosinolates (GLs). When present, the GLs were identified and quantified by HPLC analysis. 2-Hydroxy-2-methyl GL (1) was the major GL in the cork of D. euryodes. Moreover, 4-hydroxybenzyl GL (2) was the major GL in the seed of D. gossweileri whereas the bark contained 2 as the minor GL and benzyl GL (3) was the major one. In addition, 4-methoxybenzyl GL (4), 3-methoxybenzyl GL (5), and 3 were found in the root of R. subintegrifolia. However, no GL was detected in D. laciniata (leaf and stem), D. euryodes (leaf and stem), and R. woermanniana (leaf and stem-branch). Our results support the hypothesis of the existence of GLs in plants of the Putranjivaceae and Violaceae families (order Malpighiales).

Identification of Glucosinolates in Seeds of Three Brassicaceae Species Known to Hyperaccumulate Heavy Metals.

Plants from the Brassicaceae family are known to contain secondary metabolites called glucosinolates. Our goal was to establish by LC/MS the glucosinolate profile of seeds of three Brassicaceae species known to hyperaccumulate heavy metals. We investigated Alyssum fallacinum auct. non Hausskn., Iberis intermedia Guers., and Noccaea caerulescens (J. Presl & C. Presl) F. K. Mey. Our results indicate that A. fallacinum seeds contain glucoiberin and glucoibervirin, which had not been previously identified in this plant. Furthermore, we report for the first time the presence of glucoiberin, glucoibervirin, glucotropaeolin, and sinigrin in I. intermedia. We have detected for the first time glucoconringiin in N. caerulescens. In addition, glucosinalbin, 4-hydroxyglucobrassicin, and glucomoringin were also detected.

An overview on neuroprotective effects of isothiocyanates for the treatment of neurodegenerative diseases.

The discovery of new natural compounds with pharmacological properties is a field of interest widely growing, especially for the management of neurodegenerative diseases. As no pharmacological treatment is available to prevent the development of these disorders, dietary intake of foods or plant-based extracts with antioxidant properties might have beneficial effects on human health and improve brain functions. Isothiocyanates (ITCs), derived from the hydrolysis of the corresponding glucosinolates (GLs), mainly found in Brassica vegetables (Brassicaceae) and, to a lesser extent, in Moringaceae plants, have demonstrated to exert neuroprotective properties. Specifically, strong evidences suggest that antioxidant effects may be ascribed mainly to their peculiar ability to activate the Nrf2/ARE pathway, but alternative mechanisms of action have also been suggested. This review summarizes the current knowledge about the neuroprotective effects of ITCs in counteracting oxidative stress as well as inflammatory and apoptotic mechanisms, using in vitro and in vivo models of acute and chronic neurodegenerative disease. Therefore, ITCs could be regarded as a promising source of alternative medicine for the prevention and/or treatment of neurodegenerative diseases.

Long-chain Glucosinolates from Arabis turrita: Enzymatic and Non-enzymatic Degradations.

C8-C10 methylsulfinylalkyl glucosinolates (GLs), and C8-C10 methylsulfonylalkyl GLs were identified in the seed of Arabis turrita L. by HPLC-MS/ESI analysis of intact GLs. Enzymatic (with myrosinase) and non-enzymatic (thermal at 100 degrees C, and chemical at different pH) hydrolyses were performed and the volatile isolates were analyzed by GC-MS. Only the enzymatic and chemical (pH 10) degradations produced volatiles which are originating from GL degradation. GC-MS analysis showed the presence of long-chain olefinic isothiocyanates (ITCs) along with other the long-chain thiofunctionalized GL breakdown products.

Glucosinolate Diversity in Bretschneidera sinensis of Chinese Origin.

The glucosinolate (GL) profile in several plant parts (leaf, branch, bark, root, and fruit) of Bretschneidera sinensis from three geographical regions of the People's Republic of China was established for the first time by HPLC. During this investigation, benzyl GL (1), 4-hydroxybenzyl GL (2), 2-hydroxy-2-methylpropyl GL (3), and 4-methoxybenzyl GL (4) were identified. In addition, one new GL, 3-hydroxy-4-methoxybenzyl GL (5), was isolated in a minor amount from the fruit and characterized by spectroscopic data interpretation. Furthermore, traces of 4-hydroxy-3-methoxyphenylacetonitrile were detected by GC-MS analysis in the fruits, thus confirming the presence of the regioisomeric 4-hydroxy-3-methoxybenzyl GL (6). GLs 1-5 were also quantified for the first time by HPLC in the various plant organs.

Glucosinolates in two endemic plants of the Aurinia genus and their chemotaxonomic significance.

Glucosinolates (GLs) were characterized in the seed and root of Aurinia leucadea (Guss.) C. Koch and A. sinuata (L.) Griseb., and quantified according to the ISO 9167-1 official method based on the HPLC analysis of desulfo-GLs. Glucoalyssin (GAL, 1), glucobrassicanapin (GBN, 2) and glucoberteroin (GBE, 3) were the major GLs identified in A. leucadea and A. sinuata. GC/MS analysis of the volatile fractions obtained after enzyme hydrolysis showed that they mostly contain isothiocyanates (ITCs) originating from the parent GLs. On this basis and from previous reports, C-5 alkyl GLs 1, 2, and 3 can be considered as chemotaxonomic markers of the Aurinia genus.

Review on Cardamine diphylla (Michx.) A. wood (Brassicaceae): ethnobotany and glucosinolate chemistry.

ETHNOPHARMACOLOGICAL RELEVANCE: Cardamine diphylla (Michx.) A. Wood, commonly called toothwort, is a spring perennial herb belonging to the Brassicaceae family. This endemic plant of Eastern North America has been widely used by multiple American First Nations (i.e. indigenous people of North America) for food and medicine for centuries. APPROACH AND METHODS: The aim of the review is to describe the botany, ethnopharmacology, phytochemistry, and bioactivity of Cardamine diphylla. The review covers literature on Cardamine diphylla, and the alternative name Dentaria diphylla, from English and French language sources. RESULTS: Multiple traditional uses of Cardamine diphylla by American First Nations are well documented. Initial health studies showed that the tested concentrations of the extract were not toxic against brine shrimp larvae and the same extract had a weak free-radical scavenging activity. However, bioactive compounds in the form of aliphatic and indole glucosinolates and some indole alkaloids have been isolated from this plant. Ecological research regarding Cardamine diphylla-insect interactions (such as feeding and oviposition) is also available in the literature. CONCLUSIONS: The wide range of traditional uses by multiple American First Nations suggests that the antibacterial, antiviral, immunostimulant, analgesic, antipyretic, and anti-inflammatory activities of this plant should be explored in in vitro and in vivo tests. Traditional modes of preparation of the plant suggest that some of the medicinal properties could certainly be attributed to glucosinolate degradation products (i.e. isothiocyanates), but a clear assignment of active molecules and mechanisms of action remain to be elucidated. The presence of glucosinolates indicates that the plant could be probed for cancer chemopreventive properties. Overall, the review shows that more investigation is necessary to determine the possible benefits of Cardamine diphylla extracts to pharmaceutical companies as a nutraceutic specialty phytotherapeutic agent against respiratory (cold and sore throat) or gastrointestinal problems.

Updated glucosinolate profile of Dithyrea wislizenii.

Fruit extracts of Dithyrea wislizenii were analyzed for desulfoglucosinolates and intact glucosinolates using HPLC-APCI-MS and HPLC-ESI-MS, respectively. 2-Propenylglucosinolate (sinigrin) was shown to be present in the extracts. 6-Methylsulfanylhexyl- (glucolesquerellin 9), 6-methylsulfinylhexyl- (glucohesperin 10), 7-methylsulfanylheptyl- (11), and 5-methylsulfanylpentylglucosinolate (glucoberteroin 12) were isolated from the extracts and characterized by NMR and MS data. 7-Methoxyglucobrassicin was not detected in D. wislizenii extracts.

Phytoalexins from the crucifer rutabaga: structures, syntheses, biosyntheses, and antifungal activity.

Phytoalexins are inducible chemical defenses produced de novo by plants in response to diverse forms of stress, including microbial attack. Our search for phytoalexins from economically important crucifers lead us to examine rutabaga tubers (Brassica napus L. ssp. rapifera). Three new phytoalexins, named isalexin (9), brassicanate A (10), and rutalexin (11), were isolated together with five known phytoalexins, brassinin (4), 1-methoxybrassinin (5), spirobrassinin (13), brassicanal A (14), and brassilexin (15). The chemical structures of the new phytoalexins were proven by syntheses, and their biological activity against four plant pathogens were determined. Biosynthetic studies using tetra- and pentadeuterated precursors established that indolyl-3-acetaldoxime (22) and brassinin (4) are precursors of brassicanate A (10) and rutalexin (11) and that cyclobrassinin (23) is a biosynthetic precursor of rutalexin (11), whereas tryptamine (24) is not a precursor of rutabaga phytoalexins.

Probing crucial metabolic pathways in fungal pathogens of crucifers: biotransformation of indole-3-acetaldoxime, 4-hydroxyphenylacetaldoxime, and their metabolites.

Indole-3-acetaldoxime is an intermediate of crucial importance in the biosynthesis of diverse plant secondary metabolites of Cruciferae. The metabolism of indole-3-acetaldoxime to indole-3-acetic acid via indole-3-acetonitrile by fungi that cause important plant diseases in crucifers, Leptosphaeria maculans (asexual stage Phoma lingam) causative agent of blackleg disease, Rhizoctonia solani causative agent of root rot disease, and Sclerotinia sclerotiorum causative agent of stem rot disease, is described. As well, the antifungal activity of indole-3-acetaldoxime and metabolites and the synthesis and biotransformation of 4-hydroxyphenylacetaldoxime by the same plant pathogens and by an insect fungal pathogen, Beauveria bassiana, are reported.

Chemical defenses of crucifers: elicitation and metabolism of phytoalexins and indole-3-acetonitrile in brown mustard and turnip.

The metabolism of the cruciferous phytoalexins brassinin and cyclobrassinin, and the related compounds indole-3-carboxaldehyde, glucobrassicin, and indole-3-acetaldoxime was investigated in various plant tissues of Brassica juncea and B. rapa. Metabolic studies with brassinin showed that stems of B. juncea metabolized radiolabeled brassinin to indole-3-acetic acid, via indole-3-carboxaldehyde, a detoxification pathway similar to that followed by the "blackleg" fungus (Phoma lingam/Leptosphaeria maculans). In addition, it was established that tetradeuterated brassinin was incorporated into the phytoalexin brassilexin in B. juncea and B. rapa. On the other hand, the tetradeuterated indole glucosinolate glucobrassicin was not incorporated into brassinin, although the chemical structures of brassinins and indole glucosinolates suggest an interconnected biogenesis. Importantly, tetradeuterated indole-3-acetaldoxime was an efficient precursor of phytoalexins brassinin, brassilexin, and spirobrassinin. Elicitation experiments in tissues of Brassica juncea and B. rapa showed that indole-3-acetonitrile was an inducible metabolite produced in leaves and stems of B. juncea but not in B. rapa. Indole-3-acetonitrile displayed antifungal activity similar to that of brassilexin, was metabolized by the blackleg fungus at slower rates than brassinin, cyclobrassinin, or brassilexin, and appeared to be involved in defense responses of B. juncea.